“Ring around the rosy / pockets full of posies / ashes, ashes / we all fall down.”

We learned this nursery rhyme at a young age. As children, we formed a circle, held hands and danced around the circle as we sang it.

It is believed the poem was written about the Black Death.

In my lifetime, I have traveled to many countries around the world and learned different cultures, languages and customs. I have seen some of the world’s highlights, some of man’s greatest achievements, and some of the worst parts the world has to offer.

One macabre site that haunts me still is the walk I made through the catacombs of Paris. These ossuaries hold the remains of about 6 million people. It has the reputation of being the world’s largest grave. It has been a tourist attraction in Paris since 1874.

I had heard about the Black Death while studying European history in school, but it did not impress me until I saw the accumulation of the bones of 6 million victims in the Paris underground. The Black Plague is ranked as one of the three worst catastrophes in the world. The Catacombes de Paris are arranged in odd, if not macabre ways. Tibias are arranged together in pinwheel designs and skulls are stacked along the walls, interspersed with other bones. It is fascinating and suffocating at the same time.

The lasting impact is overwhelming. The experience caused me to learn more about the Black Death, Europe at the time, and the panic that reigned throughout the entire continent during the outbreak.

The disease resulted in the deaths of up to 200 million people and was most rampant in Europe from 1346 to 1353. It is believed to have originated in Asia where it traveled along the Silk Road. The bacterium was carried by black rats. The Oriental rat fleas that bit the rats then infected humans with their bites.

It can also be spread pneumonically. When the flea bites a host, it regurgitates into the wound, causing the infection. The responsible bacterium is Yersinia pestis. We actually have rodents infected with the plague that live in California. Chipmunks, squirrels and marmots, among others, are trapped and tested for the plague, and if they test positive, the areas are closed for the season. Pay attention to the signs if you see them.

The first report of the disease in Europe was in Caffa (Italy) in 1347. A ship docked there with plague patients and dead bodies. Days later, the disease had already spread into the population.

People feared the dead bodies and patients, not realizing that the bacteria were spread by the rats that came ashore bringing fleas with them. From there it spread northward. Seven years later it arrived in England where one estimate is that 90 percent of the population may have died. Current estimates range around 50 percent of the entire European population. The disease spread to Russia, to the Middle East and to Africa. The more rural regions were less affected than the crowded cities.

Most victims died within two to seven days of the initial infection, depending upon their symptoms. The Italian writer Boccaccio said about the victims, “they ate lunch with their friends and dinner with their ancestors in paradise.” Boccaccio was also the first to describe the symptoms: “The first signs of the plague were lumps in the groin or armpits. After this, livid black spots appeared on the arms and thighs and other parts of the body. Few recovered. Almost all died within three days, usually without any fever.”

Europe was inflicted with starvation as a result of the plague. Fields were not tended because the farmers died. Harvests were not brought to market because the couriers were also victims. Livestock died and villages were abandoned. People who survived believed it was a miracle from God.

The medical knowledge in the Middle Ages was not what it is now. Many things were believed to have caused the plague. The king of France blamed it on three planets that aligned in 1345. He believed this conjunction caused the “Great Pestilence.” Others believed in astrological causes, earthquakes and the poisoning of wells, among other things. It was only in the 19th century that hygiene became an issue and the streets were cleaned, live animals were contained, and human parasites were recognized.

There are two types of rodents involved in this cycle. One is the resistant rodent that is a host for the bacteria and keeps it in the cycle. The second is one that becomes infected with the disease. When the second type of rodent dies, the fleas seek out new hosts, including humans.

DNA taken from skeletons in Europe proved it was the Y. pestis bacteria that caused the plague. Protein signatures specific to this bacteria were found in the skeletons.

There have been multiple outbreaks of the olague around the world. Europe’s last occurrence was in Marseille, France, in 1720. The third pandemic in China occurred from 1855-59. The Middle East has suffered severely from the plague, and as much as two-thirds of the population in centers such as Baghdad were lost.

Without the knowledge of antibiotics, doctors in the Middle Ages relied on crude methods to treat patients such as bloodletting, boil-lancing, burning aromatic herbs and bathing the patient in vinegar and other compounds. Many times, doctors refused to see patients out of fear.

In addition to people becoming infected and dying, livestock was also affected. People believed the only way to be saved from the Black Death was to ask for and win God’s forgiveness. Thousands of people who were considered troublemakers or heretics were massacred in the name of God during this period. There were public displays of penance, and people would beat one another with whips and leather straps. The sick and dying often were abandoned out of fear. Houses and property were abandoned, and human suffering reigned over the continent.

The United States of America has not gone untouched by the plague. There was an outbreak in San Francisco from 1900 to 1904, with a second outbreak in 1907. From 1944 through 1993 there were 362 cases of human plague in the U.S. Ninety percent of these cases have occurred in California, Arizona, Colorado and New Mexico.

Today, between five and 15 people are exposed to the plague each year in the United States. We now know how to treat an infection successfully with antibiotics.

The fear, however, is that the bacterium could become drug-resistant and once again become a major health threat. This already happened in Madagascar in 1995.

Dianne Erskine-Hellrigel is executive director of the Community Hiking Club and president of the Santa Clara River Watershed Conservancy. If you’d like to be part of the solution, join the Community Hiking Club’s Stewardship Committee. Contact Dianne through communityhikingclub.org or at zuliebear@aol.com.